The present invention relates generally to current sensors, and more particularly, relates to a current derivative sensor.
The ability to detect, measure, and record a rate of current change may be critical in high-speed electronic applications. The rate of current change may be referred to as a slope of a current signal, or alternatively, as a time derivative of a current signal (di/dt). The rate of the current change may be important when accounting for unwanted noise, such as electromagnetic interference (EMI) and radio-frequency interference (RFI), generated by high-speed circuits. However, most current sensors detect and measure only the magnitude of the current, and not the rate of current change.
Often the slope of the current signal is determined using computer simulation techniques, such as finite element analysis, lumped element simulation, and behavioral modeling. These computer techniques can become computationally intensive and include limiting assumptions, which may reduce the accuracy of the simulation result. Therefore, it would be beneficial to make a direct measurement of di/dt using a current derivative sensor.
A current derivative sensor and a method for detecting, measuring, and recording a time derivative of a current signal (di/dt) are provided. A sensing element detects current. The current flows through the sensing element, generating a differential potential across the sensing element. A gain circuit amplifies and converts the differential potential to a single-ended output. An analog to digital converter converts the single-ended output and provides an output representative of di/dt.